Small diesel generators occasionally have a bad image. So many people will not even consider such a generator at the time they are trying to find out which generator suits their needs best. But in my view that is just a prejudice against diesel engines. Diesel engines have always been the most preferred engines in commercial settings. So there is much experience over a great number of years with these engines. Important issues like cost, reliability, and efficiency have been thoroughly evaluated. And if diesel technology didn’t perform well at these issues, it would already have been abandoned a long time ago. So the truth is that diesel is more reliable, more efficient, has a longer life cycle and requires less maintenance than other internal combustion engines. And in this article I will show you the technical facts that will explain how this is possible.

An internal combustion engine generates useful mechanical energy by the expansion of pressured gases at a high temperature. An important efficiency problem is that a considerable part of the energy from the fuel is lost in the heating process itself. And to make it even worse, this energy is heating up the engine so much that a part of produced useful mechanical energy has to be used for cooling down the engine in order to prevent overheating and severely damaging the engine. It is a fact hat the temperature of a diesel engine is much lower than that of any other internal combustion engines. The lower temperature indicates that less energy is lost in the heating process and less energy is necessary for cooling. So this is part of the explanation for the greater efficiency of the diesel engine.

Another factor that plays a part in efficiency of internal combustion engines is the compression rate: the higher the compression rate of an engine, the higher the efficiency will be. Well, the compression rate of a diesel engine is 14:1 up to 25:1, and the compression rate of a modern gasoline engines is between 8:1 and 12:1. Because of the efficiency the cost of using a diesel engine will be less than that of a gas engine. To be more specific: the fuel cost of a diesel generator per kilowatt is 30% to 50% lower compared to a gas generator. So this is another part of the explanation of the efficiency of a diesel engine.

And then there is the maintenance. And that is yet another reason for the popularity of diesel engines: they require less maintenance and also last longer than gas engines. Partly this is caused by to the lower temperature of the diesel engine, as we saw before. But another reason is for the reliability and the lower maintenance cost is the fact that there are no spark plugs or spark wires in a diesel engine. Spark plugs and wires not only are the cause of many malfunctions in other engines, but they have to be replaced regularly.

The last prejudice I want to talk about is the fact that many people think that diesel engines are very noisy and smelly machines. And indeed that was true - in the past. But not any longer, because the past decades diesel technology has made great progress. Diesel engines run quieter and less noisy then ever. Better insulation material have been developed (and used). And also the use of mufflers has contributed to the low noise diesel engine.

So being more efficient and less noisy then in the past, I hope you will agree that choosing a small diesel generator is indeed a choice with a future.

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